Page 28 - Energize July 2021

NEWS

The world’s easiest cable gland to fit

cable gland performs two basic functions, namely fastening the cable to the apparatus
so that it cannot pull out and also earthing the cable armouring to which it is connected.
A Cable termination manufacturer Pratley produces a uniquely adjustable cable gland for
SWA cable that fits any size armouring. The adjustability of the gland makes it “the world’s easiest
to fit,” asserts Marketing Director Eldon Kruger.
Unique to the gland is an ingenious differential nut device to ensure unprecedented clamping
force for aggressive armour anchoring. Using two lightly different coarse pitch threads, it achieves
the mechanical advantage of an ultra-fine pitch thread. The armour is sufficiently gripped when
the gland is only hand tightened. “This can be compared to the gearbox of a truck that is going
uphill in first gear. It’s like having a gearbox in a cable gland,” explains Kruger. The differential nut 25 mm. While the nipple will pass through
is also self-locking, which means that the gland is locked in the adjusted position, even under the 20 mm knock-out, the spigot will also
extreme vibration. fit a 25 mm hole. This is important because
The loose cone allows for clear visibility of exactly how the cone is fitted under the armouring. when fitting an ordinary 20 mm gland to
This is normally not achievable with fixed-cone bushes on ordinary cable glands. Occasionally with a 25 mm hole, the gland tends to shift to
an ordinary cable gland, where one cannot see what is happening with the cone, a wire strand one side and very often a corner of the lock
of the armouring can get caught under the cone. When the gland is tightened, this wire may nut slips into the hole. The worker fitting
penetrate the bedding and come into contact with a conductor. “This is no longer an issue with the gland becomes impatient, decides
the Pratley cable gland,” highlights Kruger. that the gland is tight enough and thereby
The cone bush is made from high-tensile brass, meaning the gland can be tightened as much as compromises the earth continuity and
is required without crushing or distorting the cone. Ensuring the gland is as tight as possible is critical causes a safety issue. A Pratley Adjustable
for a good grip and proper earthing over a long period. The fact that the cone is loose also makes it Cable Gland, on the other hand, always
‘self-centring’, meaning an even and uniform grip all the way round the armouring. Ordinary cable pulls up nice and evenly.
glands usually screw in eccentrically, with the grip on one side of the armouring being tighter than The Pratley Adjustable Cable Gland
on the other. However, the loose cone in the Pratley Adjustable Cable Gland will not turn and distort is also nickel-plated to reduce bimetal
the armouring. Adjustability is very important, especially when fitting large cables. When fitting a corrosion. The shroud is made from a unique,
gland, the cone pushes the armouring out, while simultaneously trying to get the threads of the two specially formulated synthetic rubber to
parts of the gland to mate. Such an operation can be frustrating when using ordinary cable glands, render the gland watertight. It will also
especially on heavier cables where the armouring is thick and difficult to work with. resist acids and oils and will be unaffected
With the Pratley Adjustable Cable Gland, simply turn back the nipple so that it does not by sunlight and UV radiation. Moreover, it
press on the cone, get the threads on the cone and differential nut to mate and then screw in fits snugly into the groove provided for it on
the nipple. By varying this adjustment, the gland is fitted correctly and fitted far quicker than a the gland. Unlike conventional glands, the
conventional cable gland, thus saving on installation time and cost. shroud covers the whole gland, meaning that
Each gland size covers a range of cable sizes, while the thickness of the armouring also varies. when it is fitted, the only exposed part is this
On an ordinary cable gland, the only place to make up for these changes is in the thread. When portion of the nut.
the maximum size of cable that will go into a given gland is reached, one section of the gland
clings to the other by only a thread or two when it is tightened up. This does not happen with the Contact Sales, Pratley, Tel 011 955-
Pratley Adjustable Cable Gland, as the same number of threads are always mated. 2190, sales@pratley.co.za, www.
Each Pratley Adjustable Cable gland size fits two knock-out hole sizes, namely 20 mm and pratleyelectrical.com

Contact Mark Yelland for all your advertising requirements:

Cell: 074 854-1597

Email: marky@nowmedia.co.za

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